Papers in PDF format

Another approach we have tested as an ASTER client-server interface uses telnet. The server is a 486 running
Linux and the client is a 486 running Windows. The user on the Windows client logs onto the Linux machine
using telnet and then runs ASTER using the normal ASTER-emacs interface. Normally ASTER sends the
DECtalk commands via the serial port to the hardware voice synthesizer. However this is useful only if the
user has direct access to the Linux machine. Instead, to get the DECtalk commands to the client, we send them
via a pipe to another process running on the server. This process then takes the DECtalk commands and sends
them through a Berkeley Socket over the internet to a process running on the Windows client. The Windows
client then sends the DECtalk commands to the synthesizer via the serial port on the client and also sends any
responses from the synthesizer back through the socket over the internet to the server. We chose a Windows
client because Windows is widely available and because, using Winsock, the client can run both telnet and the
process which redirects the commands from the socket to the serial port.
Notice that this method requires at least two processes on the server and two processes on the client. The client
is running both telnet and the socket to serial port redirection process; the server is running both ASTER and
the serial port to socket redirection process. This trick of redirecting the DECtalk commands through an
internet socket allows the user to use ASTER to read and browse through his document just as if he were
directly on the server. Note that DECtalk commands, not audio files, are being passed back and forth from the
client to the server. The bandwith needs are therefore quite small, and this type of interaction can be sustained
over a relatively slow internet connection. The main drawback is that to use telnet the user is required to have
an account on the server, unlike the Web method which allows anyone access.
Summary
Two different systems have been developed for running ASTER via a client-server interface - one an html/Web
based approach and the other an internet socket/telnet approach. The Web system would make ASTER more
generally available to the public while the telnet/socket system would permit more interactive use. Research is
being planned to merge these systems to create a single client-server method for using ASTER. This method
could then be made available to the public.
References
[1] Raman, T.V. , "AsTeR - A system for reading Technical Documents,"
Cornell University, 1995.
http://www.cs.cornell.edu/Info/People/raman/raman.html